Heney baragwanath



(No Model.)

H. BARAGWANATH.

ELEVATOR.

Patented July 12,1881t pli WHEEE'EE N. PUEHS. Pmlu-Lwhogmpher. wnshmglan. IKC.

Uivrrno STATES AND JAMES A. WILSON AND JOHN S. ROAKE, BOTH OF SAME PLAGE.

ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 244,168, dated July 12, 1881. Application filed January 15, 18H1. (No model.)

To all whom tt may concern:

Be it known that I, HENRY BARAGWANATH, a citizen of the United States, residing in Brooklyn, Kings county, in the State of New York, have invented certain new and useful Improvements relating to Elevators, of which the following is a specification.

My invention is adapted for use in manufactories, mines, and various situations; but I intend it more particularly for hoisting passengers and goods in high buildings in cities. It affords great safety and convenience of working, with unusuallyr small space and weight. It can be placed in any position at the bottom or top of a buildin g. I will show it as mounted vertically in the top of a building.

The accompanying drawings form a part of this specification and represent what I consider the best means of carrying out the invention.

Figure 1 is a front elevation, and Fig. 2 is a side elevation.

Similar letters of reference indicate corresponding parts in both the figures.

I employ two sets of sheaves of suitable size, each set mounted with liberty to turn on a single pin or shaft,each end of which is formed in a nut and fits upon a stout right-and-lefthanded screw-shaft. These shafts, being geared to a common driving-pinion, turn alike, and move the axles, and consequently the sheaves, apart and together. The wire rope, or other rope being properly fitted upon the sheaves, is worked rapidly by a slow motion of the axes. In case of accident, the friction of the screws will hold the elevator-cage in a fixed position.

Referring to the drawings, A is a drivingshaft, turned by open and cross belts (not shown) running alternately upon a fast pulley, A', and upon the loose pulleys A2 A2, as will be understood. This communicates motion to a pinion, B', which engages with larger spur-wheels D' keyed on the screw-shafts D. These shafts D are mounted parallel to each other, and are each provided with a right-hand screw-thread, d, and with a left-hand screwthread, d'. The shafts are supported in strong fixed bearings, suitable provision being made to resist the slight end strain.

Gr G, &c., are a set of sheaves mounted loosely on a stout shaft, G', equipped at each end with long and reliable nuts G2, which are preferably formed in two halves and secured by bolts, as shown. These nuts embrace the right-handed screw threads d. A corresponding set of sheaves, H, are mounted below on a stout shaft, H', and equipped with corresponding nuts, H2, which embrace the left-handed screwthreads d'.

The two ropes m are permanently secured 6o at their ends to bolts or other fixtures on the frame-work indicated by on'. They are led around the several sheaves, G H, as represented, and thence run over leading-pulleys, and are led down from the latter to the cage. (Not represented.) As both the cage and the leading-pulleys are such as are used in ordinary elevators, and as the operation of the device can be understood without their being shown, I have not deemed it necessary to show 7o these features in the drawings. Each of the sheaves Gr and H is formed, as shown, with two grooves in the periphery. The two ropes m are of equa-l length, and are led around the respective pulleys, each in the corresponding 7 5 groove, so that they run uniformly, and are taken up and let out uniformly by the motion of the pulleys. I provide, by an equalizinglever or other suitable mean-s, (not shown,) for evening the strain and compensating for any 8o slight differences in the stretch of the ropes.

Operation: The belts (not represented) are supposed to run constantly, and being controlled by a shipper, (not represented,) operated from the cage in any ordinary or suitable manner, cause the shaft A to turn in one direction or the other, and consequently to turn the screw-shafts D, both uniformly either to the right or to the left. The turning of the shafts to the right by the action of the screw-threads d d' 9o in the nuts G2 H2 causes the sheaves Grand H to travel apart, thus taking the rope m and hoisti ing the cage. At any point where it may be arrested the screws receive the strain and hold the cage reliably, independent of any action of 9 5 or connection to the engine. When by the action of the shipperl (not represented) the belts turn the shaft A in the opposite direction the screw-shafts D turn in the opposite direction,

and by the action of the screw-threads d d' in Ice t the nuts G2 H2 cause the sheaves G and H to approach each other. This motion delivers the rope m and allows the cage to descend.

Modifications may be made. I can employ only one rope m running over a correspondingly-simpliiied set of sheaves, G and H. The duplication of parts may be carried still farther than shown, so as to employ three or any other desired number of ropes, the strain on the whole apparatus being not appreciablyincreased by the division of the load between a number of ropes, while the security of the apparatus is thereby enhanced. I canin such case correspondingly increase the number of grooves on each sheave, or can supply separate sheaves, as convenience may dictate. I can use a single thread, d, on each of the screwshafts, and have only one of the sets of sheaves movable, the other being' held on alixed shaft. I can divide each set of sheaves G and H and introduce a third screw-shaft D in the center of the system with a gearing at the bottom correspondingly arranged to givcit the proper motion. I can use two or more such intermediate screw-shafts, or I can use one central screw-shaft so operated, and dispense with all the others, even with the two outside screwshafts now shown.

Among other important advantages of this invention is the superior distribution of wear and strength. Instead of, as in some previous apparatus, compelling a screw to work a wormwheel under conditions which would allow but two or three threads' to be efficient at once, and only a very small part of the circumference of those-being in contact at one time, this invention allows as many threads to be engaged as is found expedient, the number being increased by lengthening the nuts, and the several worked bearing extending quite around. With ordinary attention to lubrication the wear of this apparatus is inappreciable.

I claim as a mechanism for operating elevatorsl. The combination of one or more screwshafts, D, having right-and-left-hand screwthreads, and suitable driving-gear therefor, with two sets of sheaves, G H, and rope or ropes m, arranged for joint operation, substantially as and for the purposes herein specified.

2. In combination with the screw-shafts and travelers, the sheaves G H, having the double grooves shown and described, and the double rope m working therein, substantially as set forth.

In testimony whereof I have hereunto set my hand at New York city, N. Y., this 6th day of January, 1881, in the presence of two subscribing witnesses.

f HENRY BARAGWANATH.

Witnesses:

WM. H. SIcKLEs, WILLIAM HINE.

smoothly and uniformly in aV 

